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Efficient hydrogenation of organic compounds employing low‐cost and easy‐to‐synthesize catalysts is highly desirable as the corresponding hydrogenated products have significant importance in pharmaceutical and fine‐chemical industries. Herein, a cobalt(II) complex supported by α‐diimine ligand has been easily prepared by treatment of anhydrous CoCl2 with diimine, which can catalyze the hydrogenation of unsaturated bond with ammonia borane as the hydrogen source. A variety of ketones and aldimines bearing diverse functional groups can be reduced to corresponding alcohols and amines in moderate to excellent yields at ambient conditions. It is noteworthy that several readily reducible functional groups such as nitro and cyano are tolerated under the standard reaction conditions. Furthermore, the gram‐scale reaction has been successfully carried out and the procedure could be handled easily, which both make this methodology general and practical. [ABSTRACT FROM AUTHOR]

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Heterocycles, primarily the nitrogen-containing six-membered triazines, pyrimidines, and pyridines are used in synthesizing the active pharmaceutical synthons and natural products. Catalysis, particularly transition metal catalysis, can also be used to obtain regioselective, stereoselective, and chemoselective transformations. This review work deals with the recent advances made in metal-mediated/catalyzed synthesis of triazine derivatives and therefore will assist chemists in comprehending the issues associated with the present methods as well as future prospects, in terms of substrate and catalyst respectively. This article is of interest to a large area of organic chemists working in the field of heterocyclic productions in academia and industrial R&D sectors. Noteworthy, this assessment will serve as a guiding light to consider: (i) the importance of several transition metals employed in the method development domain and (ii) in the R&D sector for further necessary modifications. [ABSTRACT FROM AUTHOR]

A vital transition metal Cu(II) ion catalyzed reaction was encrypted in the synthesis of new coumarin tethered triazoles 6(a-i) using the substituted azidobenzenes and substituted 3-acetyl-2H-chromen-2-ones in the presence of oxidative potassium persulfate, and DMF as a solvent and C5-H source. The structure proofs of the new compounds were provided by the spectral analysis. The in vitro antimicrobial activities of the target compounds indicate that compounds 6c and 6g of the series have potent inhibition against the tested bacteria and fungi species. Among the synthesized series compound 6g was found potent for α-amylase inhibition activity. Synopsis. Dimethylformamide was used as a solvent and C5-H source reagent in the synthesis of triazole rings. The reaction of substituted azides, 2(a-e) and substituted 3-acetyl-2-oxo-2H-chromenes, 5(a-b) in the presence of a catalytic amount of Cu(NO3)2 and an oxidant K2S2O8 was carried out under reflux conditions using an oil bath for 36-48 h. From the reaction mixture, the target compounds 6(a-i) were extracted with ethyl acetate. The synthesized coumarin-triazole hybrids, 6(a-i) were spectroscopically characterized and evaluated for antimicrobial and α-amylase inhibitory activities. [ABSTRACT FROM AUTHOR]

A bio-inspired approach for efficient conversion of cellulose to formic acid ( FA) was developed in an aqueous alkaline medium. Metalloporphyrins mimicking cytochrome P450 exhibit efficiently and selectively catalytic performance in catalytic conversion of cellulose. High yield of FA about 63.7% was obtained by using sulfonated iron( III) porphyrin as the catalyst and O2 as the oxidant. Iron( III)-peroxo species, TSPPFeIIIOO−, was involved to cleave the C-C bonds of gluconic acid to FA in this catalytic system. This approach used relatively high concentration of cellulose and ppm concentration of catalyst. This work may provide a bio-inspired route to efficient conversion of cellulose to FA. [ABSTRACT FROM AUTHOR]

A general atom-economical approach for the synthesis of α-halomethyl ketones is demonstrated through Ce(SO4)2/acid co-catalyzed hydration of a wide range of haloalkynes. The reactions are conducted under convenient conditions and provide products with excellent regioselectivity in good to excellent yields, with broad substrate scope. This protocol is an alternative to conventional α-halogenation of ketones. [ABSTRACT FROM AUTHOR]

Various benzofuran bromides were dehalogenated using the palladium catalyst and phosphine ligands in the present of 5 equiv water. This set up a new and efficient protocol for the palladium-catalyzed dehalogenation of benzofuran bromides, which could tolerate the presence of water and have selective debromination. [ABSTRACT FROM AUTHOR]

The acylation of a variety of aromatic compounds with benzoyl chloride or its derivatives and catalytic amounts of Al2O3–ZrO2/S2O82− solid superacid affords the corresponding diaryl ketones in good to excellent yields 75–93% at appropriate temperature. [ABSTRACT FROM AUTHOR]